Love at first bite

By Richard Macey

THEY may be nature's ultimate eating machines, but exactly how sharks hunt and kill so easily remains a mystery.

So when a 2.4-metre great white died last September, entangled in netting at Lakes Beach on the Central Coast, scientists moved quickly.

Wrapped in plastic, the endangered species was dashed to Newcastle's Mater Hospital for a CT scan, then frozen. Researchers phoned Dan Huber, a shark expert at Florida's University of Tampa, inviting him to help dissect the fish.

With Dr Karen Moreno, from the University of NSW, he spent the day dismantling the predator, removing its muscles one by one for examination. "We are taking it apart to see how it works," said Dr Huber. "When we are done you will be left just with the cranium and jaws.

"This is the first great white I have ever worked on," added the excited scientist. "I flew half way round the world to do it."

Data from the dissection, along with a series of CT scans, will be logged into computers to create a digital shark that should reveal the animal's biological mechanics. "We want to find what they are really capable of," said Dr Huber, noting very little credible data had been collected on the great white's potential "bite force". Its hunting efficiency, he said, was based not just on its teeth, but its muscles, behaviour and streamlined body.

One mystery involved the soft cartilage forming shark skeletons. "How do they perform at very high capacity with a soft skeletal material?"

Dr Huber predicted the project could lead to new protective clothing for swimmers, and even technology to rebuild damaged human bodies. Stephen Wroe, a University of NSW biomechanics expert, said the digital shark should provide clues to the eating habits of extinct animals, including the great white's relative, the 16-metre 30-tonne megalodon that died out 1.6 million years ago.

"There is eating and having sex, that's the basis of life," said Dr Wroe. He said that by "scaling up" the digital great white they hope to estimate the bite force of the extinct monster.

Dr Huber's interest stems from childhood when a relative was attacked by a shark.